Indices of the values for which two conditions are true

I have a table of data where the first column is an abbreviated name (abbrev), second column is the first word of the full name (firstword) and the third is a particular number corresponding to that name. I would like to clean my data from duplicates that have the same 'abbrev' and 'firstword' and sum up the numbers for these duplicates. Some entries may have the same abbreviated name but a different first word- e.g. 'rr' and 'Roger' and 'Dodger' and vice versa, that's why I want to introduce this condition that both the first name and the first word have to match for an entry to be considered a duplicate.

Or in other words from this data:

abbrev =

{'yw' }

{'rr' }

{'yw' }

{'rr' }

firstword =

{'yellow'}

{'Roger' }

{'yellow'}

{'Dodger' }

number =

5

10

1

3

I want to get this:

abbrev =

{'yw' }

{'rr' }

{'rr' }

firstword =

{'yellow'}

{'Roger' }

{'Dodger' }

number =

6

10

3

Thank you in advance!

Answer 1

[Peng Li]

tbl = table(abbrev(:), firstword(:), number(:));
[gp, outTbl] = findgroups(tbl(:, 1:2));
outTbl.sum = splitapply(@sum, tbl.(3), gp)

outTbl =

  3×3 table

     Var1        Var2       sum
    ______    __________    ___

    {'rr'}    {'Dodger'}     3 
    {'rr'}    {'Roger' }    10 
    {'yw'}    {'yellow'}     6 

[Emiliya Taskova]

Peng Li, you're amazing! Thank you so much for the answer!